Snap-action pulse switch



June 10, 1969 E. 1.. LONG 3,449,538

SNAP-ACTION PULSE SWITCH Filed Aug. 7, 1967 jzg INVENTOR.

5mg L. Lam/Gr United States Patent 3,449,538 SNAP-ACTION PULSE SWITCH Eric L. Long, Highland Park, Ill., assignor to Cherry Electrical Products Corporation, Highland Park, 111., a corporation of Illinois Filed Aug. 7, 1967, Ser. No. 658,709 Int. Cl. H01h 13/56, 21/40 US. Cl. 200-160 9 Claims ABSTRACT OF THE DISCLOSURE Summary of the invention A snap-action switch having a movable blade consisting of two parts interconnected by cooperating coil spring overcentering elements which efiect simultaneous and independent movement of the parts of the blade into momentary circuit making contact position. Switches of this nature are generally classified in Class 200, Electricity, Circuit Makers and Breakers.

The invention consists in the novel combination and arrangement of parts to be hereinafter described and claimed.

The invention will be best understood by reference to the accompanying drawing showing a form of construction in which:

FIG. 1 is a side elevational view of the internal elements of the switch in their normal rest or inoperative position.

FIG. 2 is a side elevational view of one part of the movable switch blade.

FIG. 3 is a top plan view of the movable switch blade shown in FIG. 2.

FIG. 4 is a side elevational view of the second part of the switch blade.

FIG. 5 is a top plan view of the second part of the movable switch blade, and

FIGS. 6, 7 and 8 are enlarged fragmentary schematic views showing the movement and actuation between the switch blade parts above identified.

The switch of this invention is contained in a switch housing 10 comprising complementary side sections, one of which is shown at 11, which together provide an interior cavity 12.

Within the cavity 12 is a fixed terminal 13 which provides at its inner end a pair of vertically extending spaced pivot posts 14. A lug 15 is struck from the center portion of the terminal 13 to which one end of a coil spring 16 is connected.

An actuator 17 has an exposed enlarged head 18 projecting out of the housing 10, and a rectangularly shaped inner portion 19 slidable between the opposite side walls of the complementary sections in a direction normally perpendicular to the longitudinal plane of the coil spring 16. The inner portion 19 of the actuator 17 as shown in FIG. 1 rests upon the coil spring 16 and will operate to deform the same out of its longitudinal plane as the actuator 17 is caused to be depressed into the housing by any external actuating force.

Held in compression against the pivot posts 14 of the terminal 13 by the coil spring 16 is a pivot plate 20. This pivot plate 20 is formed to provide separate arm elements 'ice 21 and 22, having internal corner shoulders 23, which will embrace the opposite outer vertical edges of the pivot posts 14 in a manner well known in the art.

The opposite longitudinal edges of the pivot plate 20 are relieved as at 24 and 25 so as to provide a reduced body portion. Adjacent the forward end of the reduced body portion of the plate 20, and including the forward walls 26 which define the relieved areas 24 and 25, the body is angularly bent out of its longitudinal plane to form a depressed base 27 which has its free end wall formed at right angles to provide a vertically extending support 28. The opposite parallel vertical edges of the support 28 are notched as at 29 so that the parallelly extending legs 30 of the switch blade 31 may be disposed therein so as to connect the blade 31 to the pivot plate 20.

The switch blade 31 is generally Ushaped and provides spaced apart parallelly extending legs 30, the free ends of which are angled downwardly to provide stops 32. These legs 30 terminate into bearing shoulders 33 which abut the wall portions 34 provided by the support 28 to either side of the notches 29. The free end of the switch blade 31 is bent to provide a perpendicularly extending stop flange 35.

When the switch blade 31 is connected to the pivot plate 20 its legs 30 will be projected through the notches 29 formed in the opposite vertical edges of the support 28, and will extend into the relieved areas 24 and 25 with their stop 33 disposed beneath the rear walls 36 and 37 of the relieved areas 24 and 25. A coil spring 38 has one end connected to the blade 31 and extends through a center opening 39 formed in the body of the plate 20 and the support 28, so that its opposite end may be connected to the pivot plate 20, such as is shown in FIG. 1. The coil spring 38 will normally lie in a longitudinal plane which extends beneath the pivotal connection between the blade 31 and the notches 29 formed in the vertical edges of the support 28, thus yieldably urging the free end of the blade 31 in a downward direction as viewed in FIGS. 1 and 6, which is limited by the engagement of the stops 32 with the rear walls 36 and 37 of the plate 20. By this arrangement the jointed switch blade is normally in the position shown in FIG. 1 where the stop flange as provided by the free end of the switch blade 31 will engage a wall surface 40 which defines part of cavity 12 formed in the housing 10.

Upon actuation of the actuator 17 the coil spring 16 will be deformed out of its longitudinal plane to a point where it will, with a snap action, effect pivotal movement of the pivot plate 20 in a downward direction as seen in FIGS. 6, 7 and 8. As the pivot plate 20 so moves, it will carry with it the switch blade 31. The simultaneous movement of the pivot plate 20 and switch blade 31 continues until the contact 41 carried by the switch blade 31 engages the contact button 42 held in a fixed position within the cavity 12 by a second terminal 43, as seen in FIG. 7. The snap action movement of the pivot plate 20 under the compression forces of the spring 16 causes it to continue in a downward direction until the base 27 thereof engages a lug 46 carried within the cavity 12 by the bottom wall of the housing section 11. As this continued movement of the pivot plate 20 takes place after the switch blade 31 has engaged the contact button 42 of the terminal 43, such movement of the pivot plate 20 is independent of further pivotal movement in a downward direction of the switch blade 31. This independent movement of the pivot blade 20 relative to the arrested switch blade 31 displaces the spring 38 above the connection between the pivot plate 20 and switch blade 31, causing the switch blade 31 to be pivoted with a snap action in an opposite or upward direction until the legs 30 engage the forward 3 walls 26 of the relieved areas 24 and 25 of the pivot plate 20, as seen in FIG. 8. This opposite independent pivotal movement of the switch blade 31 separates the contacts 41 and 42, again disrupting any circuitry therethrough.

As the initial pivotal movement of the pivot plate is continuous from the position shown in FIG. 6 to that shown in FIG. '8 where the base 27 rests upon the lug 46, the simultaneous and independent movement of the switch blade 31, first in the same direction and then in an opposite direction, creates a positive momentary circuit making contact thereof with the terminal 43.

Upon removal of the external activating force from the actuator 17 the coil spring 16 will return to its original longitudinal plan as seen in FIG. 1 and carry with it the pivot plate 20. The upward movement of the pivot plate 20 will permit the switch blade 31 to also move in the same direction until its stop flange 35 engages the wall 40 which defines the cavity 12 formed in the housing 10. At this point continued upward movement of the switch blade 31 will be arrested before the pivot plate 20 has returned to its original position, thus cocking the blade 31 relative to the blade 20 into its original position as seen in FIGS. 1 and 6 where the stops 32 are in contact with the rear walls 36 and 37 of the relieved areas 24 and formed in the pivot plate 20.

While I have illustrated and described the preferred form of construction for carrying my invention into effect, this is capable of variation and modification without de parting from the spirit of the invention. I, therefore, do not wish to be limited to the precise details of construction set forth, but desire to avail myself of such variations and modifications as come within the scope of the appended claims.

Having thus described my invention, what I claim as new and desire to protect by Letters Patent is:

1. A momentary contact making snap-action switch having a terminal member providing a connection for one end of a coil spring and pivot posts providing supports for one end of a movable member held in compression thereagainst by the coil spring which has its opposite end connected to the movable member, and an actuator movable against the coil spring for overcentering the same relative to the pivotal connection between the movable member and the pivot posts to move the free end of the movable member in one direction with a snap action, wherein the improvement includes:

(a) a second pivotal member,

(b) means pivotally connecting said second pivotal member to the free end of the movable member for independent pivotal movement relative thereto and simultaneous movement therewith in one direction When the latter is moved with a snap action,

(c) circuit making means in the path of movement of said second pivotal member arresting its continued movement with said movable member in said one direction, and

(d) means connected between said second pivotal member and the movable member pivoting said second pivotal member in an opposite direction with respect to the movement in one direction of said movable member and out of contact with said circuit making means as the movable member continues its movement in one direction.

2. A momentary contact making snap-action switch as defined by claim 1 wherein said second pivotal member comprises an elongated contact bearing switch blade extending beyond the free end of the movable member.

3. A momentary contact making snap-action switch as defined by claim 1 wherein said means pivotally connecting said second pivotal member to the free end of the movable member comprise spaced parallel legs pivotally embracing certain sidewall portions of the free end of the movable member, which legs cooperate with transversely extending wall portions provided by the movable member for limiting pivotal movement of said second pivotal member relative to the free end of the movable member.

4. A momentary contact making snap-action switch as defined by claim 3 wherein said second pivotal member comprises an elongated contact bearing switch blade extending beyond the free end of the movable member.

5. A momentary contact making snap-action switch as defined by claim 1 wherein said circuit making means is a fixed terminal positioned beyond the free end of the mov able member, but in the path of movement of said second pivotal member.

6. A momentary contact making snap-action switch as defined by claim 4 wherein said circuit making means is a fixed terminal positioned beyond the free end of the movable member, but in the path of said second pivotal member.

7. A momentary contact making snap-action switch as defined by claim 1 wherein said means connected between said second pivotal member and the movable member comprises a coil spring.

'8. A momentary contact making snap-action switch as defined by claim 4 wherein said means connected between said contacting bearing switch blade and the movable member comprises a coil spring which extends in a longitudinal plane between said spaced parallel legs of said switch blade.

9. A momentary contact making snap-action switch as defined by claim 6 wherein said means connected between said switch blade and the movable member is a coil spring which extends between the spaced parallel legs of said switch blade and is connected intermediate the ends of the movable member and such switch blade.

References Cited FOREIGN PATENTS 315,597 3/1934 Italy.

ROBERT K. SCHAEFER, Primary Examiner.

D. SMITH, JR., Assistant Examiner.

U.S. C1. X.R. ZOO-67 

